Circuit breakers and tank lifting assembly therefor



K. H. DATE 3,233,069

CIRCUIT BREAKERS AND TANK LIFTING ASSEMBLY THEREFOR Feb. 1, 1966 2Sheets-Sheet 1 Filed June 12, 1965 K. H. DATE Feb. 1, 1966 2.Sheets-Sheet 2 Filed June 12, 1963 r V 5 Z M Z WDWfi 4 /m!|l.1\ 0% N. vz IJW, V J\ \W/ 5 5%1 m who 0 f 7 M. Q

United States Patent 3,233,069 CIRCUIT BREAKERS AND TANK LIFTINGASSEMBLY THEREFOR Kazuo Henry Date, South Milwaukee, Wis., assiguor toMcGraw-Edison Company, Milwaukee, Wis., a corporation of Delaware FiledJune 12, 1963, Ser. No. 287,438 Claims. (Cl. 200-150) This inventionrelates to circuit breakers and more particularly to a tank litter andsupport assembly for a polyphase circuit breaker.

In three phase oil immersed circuit breakers each of the threeinterrupting assemblies are sometimes disposed in an individualoil-filled tank to minimize interphase flashover and to allow theservicing of the phases individually.

In prior art assemblies having three tanks, a tank lifter mechanism wasprovided to individually raise and lower the oil filled tank in eachphase. Such assemblies lacked flexibility becauseonly a single phasecould be serviced at any one time thereby lengthing the time requiredfor certain maintenance procedures. On the other hand, threephasemechanisms employing a single tank often unnecessarily exposed eachphase when such exposure was not required.

t It is a primary object of the invention to provide a tank lifterassembly for polyph'ase circuit breakers having an individual oilfilledtank for each phase wherein a tank lifting and supporting mechanism cansimultaneously raise orlower any given number of tanks.

A more specific object ofthe invention is to provide 'a three-phasecircuit breaker assembly including a supporting frame, a circuit breakerunit having a cover assembly fixedly mounted adjacent the upper end ofthe supporting frame and three tanks, wherein each of the tanks isassociated with one of the phases and is releasably securable to thecover assembly, and a rack assembly is mounted on the supporting framefor movement into and out of supporting engagement with each of thetanks so that each of the tanks may be individually orcollectivelysupported on the rack assembly upon release from the coverassembly for vertical movement in the supporting frame.

These and other objects and advantages of the instant invention willbecome more apparent from the detailed description thereof taken withthe accompanying drawings in which:

. FIG. 1 is a perspective view, with parts broken away, of a circuitbreaker assembly incorporating the instant invention;

FIG. 2 is a side elevational view, with parts broken away, of themechanism shown in FIG. 1;

FIG. 3 is a fragmentary, View, partly in section, of means for securingthe tank and head assembly of the mechanism shown in FIG. 1;

FIG. 4 is a view taken along lines 44 of FIG. 3;

and

sembly 12. The mounting frame assembly 12 includes four vertical cornerposts 13, a plurality of generally horizontal end members 14 joined tothe adjacent corner .posts 13 at each end of the frame assembly 12 andthree side members 15 extending horizontally along each side of theframe 12 for joining the corner post members 13 along each side. It willbe understood by those skilled in the art that the corner posts 13, theend members 14, and the 'ice side members 15 may be of suitablestructural steel angle members and may be joined in any manner wellknown in the art, such as welding.

Each phase of the circuit breaker 10 has a pair of terminal bushings 17extending through a cover or head assembly 18 which includes threesections 19 rigidly mounted in an aligned abutting sealed relation toeach other and to each of the uppermost of the side members 15 by aplurality of bolts 20.

Each phase also includes a tank 22 which is filled with a suitabledielectric fluid 23 such as oil. The lower end of each bushing 17extends below the surface of the oil 23 and has a phase conduct-or 25extending from its lower end to connect with the circuit breakerscontact structure (not shown) which are disposed in a suitable arcinterrupting assembly 26 suspended from the head 18 by insulatingstringer members 28. An insulating link 30 extends downwardly from thecover assembly 18 to en gage the contact assembly (not shown) at itslower end so that the contacts may be opened by an operating mechanismwhich is disposed in a cabinet 32 affixed to the support frame 12 andwhich has an operating member (not shown) extending from the housing 32to the hood 18 for engagement with the upper ends of the links 30.Switch operating mechanisms suitable for use with the disclosed circuitbreaker are well known in the art and, accordingly, will not bediscussed in detail for the sake of brevity. For a detailed descriptionof such an operating mechanism reference is made to co-pendingapplication Serial No. 287,439, filed June 12, 1963.

Each of the tanks 22 is releasably securable to the cover 18 by fourstud assemblies 34 which are equidistantly spaced around the upperperiphery of each tank 22. The stud assemblies are shown in FIGS. 3 and4 to include a generally U-shap'ed bracket 36 which is suitably afiixedat its ends to the tank 22 and which has a pair of opposed rectangularlyshaped apertures 38 formed at each of its sides 39 for loosely receivinga generally square peg 40. The peg 40 has an internally threadedaperture 42 whose axis is generally parallel to the sides 39 of bracket36 and which receives the lower threaded end of an elongate stud 43.After the stud 43 has been threaded into the aperture 42 the oppositesides of the block 40 are deformed at 45 to prevent the removal thereof.A cotter pin 46 extends through aligned openings 47 in the bracket sides39 and adjacent the stud 43 to limit movement of the block 40 in theapertures 38.

Four integrally formed lugs 49 extend from each of the head sections 19and adjacent each of the tanks 22 and each lug 49 has an elongate bore50 for receiving the upper end of one of the studs 43. A nut 52,threadably received on each of the upper ends of the studs 43, afiixeseach of the tanks 22 in position below its associated cover section 19.

Each of the cover sections 19 has an annular rim 54 provided with acircular continuous groove 55 for receiving an O-ring gasket 56 which iscompressed by an outturned flange 57 at the upper end of each of thetanks 22 so that the interior of each of said tanks will be sealed whenthey are in their operative position.

Referring again to FIG. 1, a tank lifter assembly 60 is provided insupporting frame 12 for moving the tanks 22 relative to the coverassembly 18. In general, the tank lifter assembly includes a rectangularframe 62 which is constructed and arranged to supportingly engage thetanks 22 and a Windlass assembly 64 which is mounted on the supportingframe 12 and is operative to move the rack 62 vertically.

The rack 62 consists of a pair of side members 66 and a pair of endmembers 67 which are suitably joined to form a rigid rectangularassembly. Three spade type studs 70 extend upwardly from each of theside members 66, and each is engageable with one of a pair of hangerbrackets 72 affixed to each of the opposite sides of the tanks 22. Asseen more particularly in FIG. 5, each bracket 72 includes a pair ofspaced-apart side pieces 73 athxed to the wall of its tank 22 and across piece 75 which interconnects the side pieces 73 and which isengageable by the lug 70. As seen in FIG. 1, the sides of the lugs 70are each bevelled to facilitate engagement between the side plates 73 ofthe hanger bracket 72.

The Windlass 64 includes a gear box 78 affixed to one of the sidemembers of the supporting frame 12 and having a pair of operating shafts80 extending from each of its opposite sides and parallel to the sidemember 15. The operating shafts 80 are each journalled at their outsideends on the arms of a U-shaped bracket member 82 atlixed adjacent theends of the side member 15. A drum 83 is affixed to each from theoperating shafts 80 and each is disposed between the arms of one bracketmember 82, and each has one end of a cable 85 wound therearound.

As seen more particularly in FIG. 2, each of the cables 85 extends fromits drum 83 upwardly and around a pair of sheaves 86 and S7 rotatablymounted in spaced relation on the uppermost end members 14. Each of thecables 85 extends downwardly from the sheaves 87 and around a pulley 88rotatably mounted on the end members 67 of the rack 62, and thence fromthe pulleys 88 upwardly where they are afiixed to the uppermost endmembers 14 adjacent the sheaves 87.

It'can be seen from the foregoing that when the windlass operatinghandle 90 is rotated in one direction each of the cables 85 will bereeled-in to move the rack 66 upwardly, and when the operating handle 90is rotated in the opposite direction each of the cables 85 Will bereeled-out to lower the rack 66.

When it is desired to lower any of the tanks 22, the rack 66 is raiseduntil each of the lugs 70 is in engagement with its associated hangerbracket 72. The nuts 52 which engage the four studs 43 on the tank to belowered are then removed so that the tank is no longer supported by thelugs 49 on the head section 19. This transfers the entire weight of thetank 22 to the rack 62 and'completely disconnects said tank from itshead section 19. The operating handle 90 is then operated in a directionwhich moves the rack 66 downwardly thereby lowering the tank 22 whosephase requires servicing.

It will be appreciated that if it is desired to lower the tanks 22 ofmore than onephase, then each can be similarly unfastened from itsassociated head section 19 and the tanks simultaneously lowered. It cantherefore be seen that each of the tanks may be lowered individually, ormore than one can be lowered simultaneously. After one or more of thetanks 22 have been lowered they can be raised simultaneously by rotatingthe operating handle 96 in the direction which raises the rack 66.

Referring again to FIG. 3, the lower end of' the bore 50 on the lug 49is shown to be flared outwardly at 90 to facilitate alignment with thestud 43. Also, to facilitate alignment between the gasket 56 and theflange 57 on the upper end of the tank 22, each of the head sections 19has an annular downwardly extending shoulder 92 and an outwardly flaredsurface 93 adjacent the rim 54.

When only a single embodiment of the instant invention has been shownand while the invention has been described with respect to oneparticular type of circuit breaker assembly, it is not intended that theinvention be limited thereby, but only by the scope of the appendedclaims.

I claim:

1. A three-phase circuit breaker assembly, including a circuit breakerunit and a supporting frame, said circuit breaker unit having a coverassembly fixedly mounted adjacent the upper end of said supportingframe, three tanks, each of said tanks being associated with one of saidphases and each being individually releasably securable in a sealedrelation against said cover assembly, and a unitary rack assemblysupported by said frame and disposed for movement into and out ofsupporting engagement with each of said tanks, so that each of saidtanks may be individually or collectively supported on said rackassembly upon release from said cover assembly for vertical movementrelative to said cover assembly.

2. A three-phase circuit breaker assembly, including a circuit breakerunit and a supporting frame, said'circuit breaker unit including a coverassembly fixedly mounted adjacent the upper end of said supportingframe, three tanks, each of said tanks being associated with one of saidphases and each being individually releasably securableto said coverassembly, and a unitary rack assembly mounted on said supporting framefor vertical movement and having tank engaging means movable intosupporting engagement with each of-said tanks upon upward movement ofsaid rack assembly and movable out of engagement therewith upon downwardmovement of said rack assembly when said tanks are secured to cover headassembly, so that each of said tanks may be individually or collectivelysupported on said rack assembly upon release from said cover assemblyfor vertical movement in said supporting frame.

3. A three-phase circuit breaker assembly, including a circuit breakerunit and a supporting frame,,said circuit breaker unit= including acover assembly fixedly mounted adjacent the upperend of said supportingframe, three tanks, each of said tanks being associated with-one of saidphases and each being cooperatively engageable with said cover assemblyin'a sealed relation, a plurality of tank securing means associated witheach of said tanks and said cover assembly for individuallyreleasablylsecuring said tanks to said cover assembly, a unitary rackassembly mounted for vertical movement on said supporting frame andhaving engaging means adjacent each of said tanks, and support means oneach of said tanks and disposed for supportingengagement by saidengaging means upon vertically upward movement of said rack assembly sothateachof said tanks maybe individually or collectively supported onsaid rack assembly upon the release of itsassociated tanksecuring means,whereby said tan-ks may be.

individually or collectively moved into or out of sealing engagementwith said cover assembly.

4. A three-phase circuit breaker assembly, including a circuit breakerunit and a supporting frame, said circuit breaker unit including a coverassembly fixedly mounted adjacent the upper end of said supportingframe,-three tanks, each of said tanks being associated with one of saidphases and each being cooperatively engageable in a sealed relation withsaid cover assembly, a plurality of stud means extending from'one ofsaid tanks and said cover assembly, a plurality ofreceiving means on theother of said tanks and said cover assembly for cooperatively engagingsaid stud means, means for releasably securing each of said stud meansin said receiving means, a unitary rack assembly mounted for verticalmovement on said supporting frame and having hanger engaging meansadjacent each of said tanks, and hanger means on each of said tanks anddisposed for supporting. engagement by said hanger engaging means uponvertically upward movement of said rack so that each of said tanks maybe individually or collectively supported on said rack assembly upon therelease of its stud means from their stud receiving means, whereby saidtank may be individually or collectively moved into or out of sealingengagement with said cover assembly.

5. A three-phase circuit breaker assembly, including a circuit breakerunit and a supporting frame, said circuit breaker unit including a coverassembly fixedly mountedadjacent the upper end of said supporting frame,a pair of terminal bushings for each phase and extending through saidcover assembly, switch means and current interrupting means for eachphase supported below said cover assembly and connected to said terminalbushings, three tanks having a dielectric fluid disposed therein, eachof said tanks being constructed and arranged to receive one of saidswitch and current interrupting means and to cooperatively engage saidcover assembly in a sealed relation, a first plurality of securing meansmounted on each of said tanks, a second plurality of securing means onsaid cover assembly for selectively relcasably engaging said firstplurality of securing means, means for releasably securing each ofassociated ones of said first and second plurality of securing means, aunitary rack assembly mounted for vertical movement in said supportingframe and including a pair of substantially parallel side members havinghanger engaging means extending upwardly therefrom and being disposedadjacent the opposite sides of each of said tanks, and hanger meansafiixed to the opposite sides of each of said tanks and each having avertical opening disposed for supporting engagement by one of saidhanger engaging means upon vertically upward movement of said rack andbeing disengageable therefrom upon downward movement of said rack whensaid first plurality of securing means are released from said secondplurality of securing means, so that each of said tanks may beindividually or collectively supported on said rack assembly upon therelease of the securing means associated therewith, whereby said tankmay be individually or collectively moved into or out of sealingengagement with said cover assembly.

References Cited by the Examiner UNITED STATES PATENTS 2,357,603 9/1944Pinkharn et al 200150 3,008,016 11/1961 Mercier 200- FOREIGN PATENTS490,586 1/1930 Germany.

KATHLEEN H. CLAFFY, Primary Examiner.

BERNARD A. GILHEANY, Examiner.

1. A THREE-PHASE CIRCUIT BREAKER ASSEMBLY, INCLUDING A CIRCUIT BREAKERUNIT AND A SUPPORTING FRAME, SAID CIRCUIT BREAKER UNIT HAVING A COVERASSEMBLY FIXEDLY MOUNTED ADJACENT THE UPPER END OF SAID SUPPORTINGFRAME, THREE TANKS, EACH OF SAID TANKS BEING ASSOCIATED WITH ONE OF SAIDPHASE AND EACH BEING INDIVIDUALLY RELEASABLY SECURABLE IN A SEALEDRELATION AGAINST SAID COVER ASSEMBLY, AND A UNITARY RACK ASSEMBLY INTOAND OUT OF SUPPORTING ENGAGEDISPOSED FOR MOVEMENT INTO AND OUT OFSUPPORTING ENGAGE-